BackgroundIn Sweden in 2002 it was discovered that the human neurotoxin acrylamide, classified as a probable human carcinogen by the International Agency of Research on Cancer (IARC), is formed during heat treatment of starch rich food. These findings caused a lot of concern among consumers, retailers, authorities, - and within the food industry itself.

Acrylamide has proven to be a carcinogen in experimental animal trials. Results from long-term animal studies carried out by the U.S. Food and Drug Administration (FDA) is expected in 2008.

In the Nordic countries the consumption of heated potato and cereals is relatively high compared to the rest of the world. We have a strong tradition in eating bread, - especially crisp bread.Therefore the NORDACRYL project focused on acrylamide in cereal and potato products.

This project has been quite unique since otherwise competing food industries have collaborated by exchanging information related to processes and products.

ObjectivesThe main objective was to determine the influence of precursors regarding acrylamide formation in potato and cereals, and to develop methods for monitoring the bioavailability of this neurotoxin. This is to be added to the evaluation of possible health effects. The objectives were achieved in laboratory models, as well as in industrial scale processing experiments.

Conclusions

It has been shown that reducing sugars such as glucose and fructose (but not sucrose) are the most common contributors (precursors) to acrylamide formation by heating.

It has further been shown that the constituent that most strongly affects the acrylamide formation in cereals is the naturally occurring free amino acid asparagine (limiting substrate).

For cereals the asparagine content in the flour is quite constant during storage, but might vary between different types of cereals and their milling fractions, highest in the bran.

For some products the additions of glycine or asparaginase contribute to reducing the acrylamide formation during baking.

For potato the limiting substrates are reducing sugars. Their increases during storage then introduce some difficulties and potentially quite large variations in the final products. Sugars in potato can be reduced by hot water treatment (blanching) and thereby lower acrylamide formation upon frying or baking.

The bioavailability of acrylamide has been investigated in a muse model system and some biomarkers have been identified.